Flat knitting machine



Dec. 25, 1934. K.-W. LiEBERKNEQHT 1,985,295

FLAT KNITTING MACHINE Filed Jain 24, 1-955 INVENTOR BY QWTZDRNE'J 7Patented Dec. 25, 1934 UNITED STATES FLAT KNITTING MACHINE Karl WilliLieberknecht, Oberlungtvits, Germany,

assignor to Kalio Inc., New York, N. Y., a corporation of New YorkApplication January In Germany 4 Claims.

Fiat knitting machines designed for use with spring beard needles aresometimes provided with a needle bar divided into sections, the centralsection being swingable or otherwise removable 5 from knitting positionin order that the knitting of certain parts of the fabric can besuspended without removing the fabric from the needles of that sectionwhile the knitting of other portions is performed on the other sections.For example, in knitting single unit stockings, a needle bar of thiskind is sometimes employed in which the section of the needle bar whichcarries the needles which knit the instep may be removed from knittingposition as above described, the object being to retain the instepportion upon the needles while the heel tabs are knit upon adjacentsections of the needle bar so that at the proper time the instep can bebrought back into knitting position simply by swinging the movablesection of the needle bar back into knitting position.

A sectional needle bar of this character having a central section whichis swingabie out of knitting position is described, for example, inPatent No. 1,901,757 issued to Karl Richard Lieberknecht. While a needlebar of this character possesses several advantages, it also has onedrawback, namely, that while the heel tabs are being knit the previouslyknit loops of the instep portion are hanging on the needles and aresupported by the knockover bits.- Since the needles have been swung outof their normal position, a greater tension than normal is imposed uponthe loops and they are continually struck by the knockover bits, withthe result that they are aptto be distorted and enlarged and evenbroken, all of which, of course, is objectionable and detrimental to theproduction of high grade fabric.

By this invention I retain the desirable features of the sectionalneedle bar and eliminate the undesirable ones. and I accomplish theseends in an extremely simple manner which leaves practically no'danger ofimproper operation and consequently imperfect knitting.

The nature of my invention is described in the following specificationand illustrated in the accompanying drawing, of which Figure 1 is afront elevation of the needle bar of my invention;

- Fig. 2 is cross-section thereof along the line 'A--A of 1; and

Pig. '3 is a fragmentary view of a detail modiiication of Fig. 2:

Fig. 4 is a similar cross-section showing the 24, 1933, Serial No.653.270

February 19, 1932 action of the central section of the needle bar at thetime of press during the knitting of the heel tabs.

For the sake of simplicity, I have confined the following description toa hosiery machine. It 5 will be understood, however, that the inventionis applicable to any flat knitting machine and the knitting of anyfabric thereon in which the knitting of certain sections is suspendedduring the knitting of others. I a

The needle bar is composed of a main section 1 and a movable centralsection 3. The needles which are employed in knitting the instep arecarried upon movable section 3 and the remaining needles upon the mainsection 1. The cen- 15 tral section 3 is pivoted to the needle barsupport as at 2, so that it may swing forward. Normally, the needles ofcentral section 3 are in alignment with the rest of the needles. Theymay be held in that position by means of a suit- 20 able latchconsisting, for example, of a. spring pressed bolt 5 on the main needlebar 1, which engages with a surface 11 on the central section 3.Preferably, the engaging surfaces of this latch are beveled, as shown.-so that the bolt will I6 have a tendency to urge the central section ofthe needle bar backward and maintain it in alignment. Irrespective ofthe bolt, however, I provide other means which will tend to maintain thecentral section 3 of theneedle bar in alignment with the other sections,but which at the same time will'pennit it to swing out of alignment atcertain times. This consists of spring 6, one end ofwhich is attached toan arm! on central section 3 and the other end of which 35 l is attachedto some stationary part of the machine such as the needle barsupport 8.

If'bolt 5 is disengaged from central section 3, this section will stillbe urged backwardly, and into alignment with the other sections through40 the action of spring 6. However, if the needles of central section 3are opp s d by any force greater than that of. spring 6, central sectionalready described. It may be accomplished to better eifect by the deviceof this invention. When the time comes for suspending the knitting ofthe instep portion during the knitting of the heel tabs, bolt 5 iswithdrawn, unlocking the central section of the needle bar. When theneedle bar is rocked backward to bring the beards of the needles againstthe presser edge, the needles of the central section will rock withthose presser edge. However, the strength of spring 6 is less than thecombined resistance of ,the beards of the needles of central section 3,so that when these needles strike the presser edge their beards will notbe closed. Instead, the entire central section will remain substantiallystationary while the remainder of the needles go to press, the centralsection simply rocking upon its pivots 3.

when the pressing oil of the other needles is completed and the needlebar reassumes its normal position, the needles of the central sectionagain align themselves with the others. Thus, the loops upon theneedles' ofj thecentralsection are retained without stretch-p ingor-distorting them to any appreciable extent cbrl equently, withoutsubjecting them ,toany undue strainthrough contact with the knock H overbitswhen'under abnormal tension. 1 When-(her when said first-mentionedmaintaining means is retracted, that the beards of the needles thereofwill not close when the needles of all the I all off-the needles oi allthe sections are required to knit in unison in the normal way, the

central section may be locked by the latch al-- ready described .so thatthe entire needle bar becomes a single operating unit.

Some means will, of course, be provided for insuring that the centralsection of the needle bar when swung back will be in alignment with theother sections of the bar. This may be'a set screw 9 passing throughcentral section .3 and engaging the main needle bar. By screwing thisset screw in or out the alignment of the needles of section 3 may bevaried.

It will be understood, of course, that spring 6 may be replaced by acounterweight or any 5 other suitable device for maintaining the desiredtension upon central section 3. Such a counterweight is shown at 6 inFig. 3.

Bolt 5 may be operated as above described by any suitable means such,for example, as that shown and described in the patent of Karl RichardLieberknecht, No. 1,899,577, which also relates to a sectional needlebar. As shown therein and in the drawing hereof, bolt 5 may be providedwith a pin lo'adapted to engage with a rod 11 mounted so as to belongitudinally slidable in brackets 12 on the main needle bar 1. Rod -11is provided with an upwardly curving cam surface 12* adapted to engagewith pin 10. When'the highest portion of this cam surface is in engage-.go ment with pin 10, the bolt will be urged upwardly into engagementwith the central section 3 of the needle bar by its spring. When the rodis laterally shifted, pin 10 will be forced downwardly, carrying-bolt 5with it and the central section of 55 the needle barwill be unlocked.The shifting of rod 11 may be accomplished by any desiredmeans-mechanical or-manual-that shown being a hand shaft 14 connected torod 11 by arms l3. Longitudinal movement of shaft 12 will effect 70 thecorresponding movement of rod 1 l.

By this invention I have retained the advantages and overcome thedisadvantages of the sectional needle bar having a section which isswung and maintained out of knitting position, and at .l. the same timeIhave'also avoided use of any of the other sections and will engage withthe loops from the" devices which will prevent certain needles fromgoing to press during the pressing of the rest of the needles byspringing them out of alignment, which puts abnormal strains on them.

In short, no appreciable strain is put upon either the fabric or themachine of my invention, since all of the needles remain in alignmentall of the time with the exception of when the needles of the centralsection are swung slightlyout of alignment, when they contact with thepresser edge. This and the fact that I accomplish my objects through anextremely simple structure is a matter of great practical importance,both to the manufacturer and user of the knitting machine.

What I desire to seek by United States Letters Patent is:

1. In a flat knitting machine having a presser bar, a needle barsupporting spring beard needles and having a section thereofv which isswingable out of knitting position, means for maintaining said swingablesection in an aligned position with the other sections of the needlebar, means for retracting said last mentioned means to release saidswingable section from its aligned position, and

additional means to maintainsaid swingable'section in an alignedposition with respect to the other sections of the needle bar in such amanneedles of the swingable section in alignment with the other sectionswhen the first mentioned alignment maintaining means is retracted, saidspring having a resilient strength less than the combiner .40 forretracting said last mentioned means, and ,means comprising a spring formaintaining the resistance of the beards of the needles of the movablesection so that when the needles of allthe needle bar sections arepressed against the presser bar in a knitting operation of the machine,the beards of the needles of the movable section will .not close andwill be positioned out of alignment with the beards of the needles ofthe other section. 3. In a flat knitting machine having a presser bar, asectional needle bar supporting spring beard needles and having onesection thereof capable of movement so that needles thereof may be movedout of alignment with the needles of other sections, means tomaintainsaid movable section normally in alignment with the othersections of the needle bar, and additional means associated with themovable section to resiliently maintain it in an aligned positionwith'respect to the other sections in such a manner that atpredetermined times when the normal aligning maintaining means isretracted, the movable section will be forced out of alignment with theother sections, as the needles of all the sections are pressed againstthe presser bar in a knitting operation of the machine to such an-extentthat the beards of the needles of the-movable section will not be closedby said pressing operation.

4. In a flat knitting machine, having a presser bar, a sectional needlebar supporting spring beard needles and having one section thereof. ca-

pabIe of movement out of alignment with the other sections, means foradjusting the alignment of said movable section with the other sectionsof the needle bar, means to maintainsaid movable section in any adjustedposition, means for retracting said last mentioned means to release saidmovable section from its aligned position, and additional meansassociated with the movable section to resiliently maintain it inaligned position with respect to the other sections when the firstmentioned alignment maintaining means is reracted and so that when theneedles of all the sections are pressed against the presser bar themovable section will be forced out of alignment with the other sectionsto such an extent that the beards of the needles of the movable sectionwill not be closed by this pressing operation. KARL WI LLI LIEBERKNECHT.

